Relocation of Holding Tank Fall 2016

Having the old holding tank ruptured and realizing any attempt at repair was likely to be a fruitless endeavor, I looked at all the options I had observed from the various members on this board who have encountered the same challenge. The best option is Jeff's of putting it in the head under the sink/laundry hamper. But that looked complicated beyond my time available to do this. I looked at Jim Cleary's forward water tank option. I didn't want to give up the water storage. Both options look great but would entail a significant degree of running pipes and/or hoses; as I have read many times before, everything on a boat, an boat, is a compromise of varying degrees. I looked at Lee's tank that he placed under the port salon seat. I opted for that for several reasons: as storage goes, its inconvenient to get anything out of there; we only kept spare antifreeze and oil, and spare hose, rags (clean) and some old rope. I could easily move that elsewhere. It also kept the run of the waste heading aft, and after measuring it out, would give me somewhere around 15-19 gallons (I have now measured it to hold 16 gallons with room to hold at least 1-2 gallons more). Because I found a way to run it under the floor of the galley with only a slight upward run to the wet locker/macerator, and the level of a full tank would be higher than the Y-valve in the locker, I felt that priming the macerator would not be a problem as it's a shorter lift than the original holding tank. It also gave me the ability via the pVC valve aft of the tank to keep the PVC pipe empty until I wanted to pump out or pump overboard, and because I used schedule 40, there is very little sanitation hose in the salon or wet locker to sit with waste in it to permeate and create odors. And lastly, I was able to leave the macerator, it's wiring, the deck pump out, etc. intact with no additional deck holes or added wiring runs. I didn't seek advice ahead of time except from Lee Nicholas and I comparing notes, but I think I have a good design that will rectify the original holding tank issue, not give up a huge amount of storage space (I can still use the aft most corner storage locker under the settee and about half of the forward portion of the under settee storage that is forward of the tank). Like Lee's design, I installed a brass piano hinge down the outboard run of the seat top, however, I wanted to retain a 'stock' look so I left the original deck and the lids intact and even replaced the teak trim that runs fore and aft on the edge of the plywood seat bottom and I screwed down the plywood using original holes and screws. Other than the piano hinge and the cut vinyl liner, you'd be hard pressed not to think this was how it came when new, well, sorta anyway! Hopefully you can follow my pictures as they are mostly chronological, starting with the video at the bottom of the gallery that shows the leak from the old keel tank and then moving forward as I cut the plywood out, ran the PVC and put it all together. I also opted to use spare PVC, a sweep 90 degree fitting and a PVC flare fitting to run forward into the head area so as to not have any sanitation hose on that end either and plan to put some type of plastic wrap around the PVC and grey hoses and wires that run thru the aft head/shower bulkhead and into the salon so as to block airflow (you can tell I'm about over and done with smelly salon/sette area!).... Thanks to Lee Nicholas for his constant, dogged encouragement, as I had some issues getting the PVC joints not to leak (never really worked with it before). However, I ran a red food coloring dye test with freshwater and it is leak free now and hopefully it stays that way. At least not if it ever leaked, I can fix it. The old holding tank was a great usage of the area, but was a construction/design flaw in my humble opinion. It left you few/not many options if it ever was compromised. I hope this helps some other fellow sailor who loves their boat but has the holding tank issue.... this is perhaps another option for you to consider to fix this nagging problem!

Than you John you really did not have to give me any credit , you did all the work. I do wish you had put a clean out port in your tank top. I know it sure is nice not to have any head smell in your boat any more . Job well done .

@schlepper

John, really appreciate your guidance on this issue. I don't know the history on the boat and why the previous owner disconnected the original HT plumbing. All the plumbing is still in place so I wanted to confirm that the HT had in fact failed. I filled the original HT thru the pump out to confirm whether it had in fact failed. So far it seems to be holding water. Any other test I should perform? If I determine it is necessary to abandon the old HT, how do you suggest sealing it off properly and do I need to fill it with something? If I do put in a new HT, I have a question about your setup. I do not know where my macerator used to be. In your pictures you show the macerator pump in the wet locker. Is that the outflow thru-hull in the wet locker? Mine is under the head sink. Also, is that an A/C water filter in front of the macerator ? Mine is under the head sink too.

Hey Mark,
Yes, my macerator and thru hull fitting for overboard discharge is in the wet locker to starboard. The a/c raw water pickup and strainer are in there too. It makes for a pretty tight setup in there but fortunately, I don't have to do a whole with those except occasional hose replacement or to clean the strainer basket, or pour some Barnacle Buster in there to clean that out of any grass, barnacles, etc. that take up residence in there. As for the old tank, I put a threaded PVC pipe caps on the vent line and the tank level sensor (i cut it off and removed the sensor). As for the fill and the pump out PVC pipes, I glued PVC caps on the pipes (they are different size pipes btw!). As for sealing it for any cracks/delamination of the glass tabbing there, I pumped out everything I could reach, down to maybe 2-3" of sludge in the very bottom. I then dumped a bunch of anti-odor holding tank chemical in there, and that was it. I did not fill it with anything. Lee Nicholas on this board, filled his with closed cell foam. I may do that at some point, but at this point, not ready to do that yet. I have other projects under way now!